Tims 66 Cuda
Mopar mid life crisis
I always told wiggle the valve off the seat. Should be .002 to .005 clearance. Dip stem in motor oil, if play goes away your good.
Tim
Tim
Curious, how do YOU check valve guides with the "wiggle" test?
- Thread starter 318willrun
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On my last set of EQ heads I bought ("out of the box/ ready to install" Bull$#!t!!!) they did the guides too tight, had #4 exhaust valve hang open and kiss the piston, bend valve. less than 3 hours run time and 6 miles after install. Id save the "wiggle test" for the old school machinist that has been doing headwork for a few years or more.
I understand and appreciate years of experience but I did use a dial indicator set up perpendicular to the valve. The heads are new so I doubt there is any taper to the guide. I'll try tomorrow with oil as suggested.
gregcon
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One of the miracles of the internal combustion engine is the valve guide, and the fact that it works at all. We don't supply it with direct oil pressure, and we also put a dedicated seal on it to keep even more oil out. Then, we slide it 2 or 3,000 times per minute and at very cold and very hot temperatures and....it lasts many decades and thousands of miles.
moper
Well-Known Member
The 340 I have for sale is using heads from another engine because the heads on them t were so bad. Like visibly ovalled. No wiggling required... lol
Worst I’ve ever seen, and they got tossed in the scrap pile.
Worst I’ve ever seen, and they got tossed in the scrap pile.
I do the wiggle test but not on valve guides. It keeps Kitty happy.
I bet she is just a purring. Kim
I've honed out 1,000 or so guides and measured them with a dial bore gauge. Then installed the valve and wiggled it. Got a pretty good feel for them now.
But I still need to check w/ the dial bore gauge and make sure I'm not getting them tapered.
But I still need to check w/ the dial bore gauge and make sure I'm not getting them tapered.
famous bob
mopar misfit
But.... follow me before you correct me........ Your tolerances are to make "better than new". Your a machinist that cares and takes pride in your work, no expenses barred. So, this may be very difficult for one such as yourself. However, picture a guy at home, that pulls the heads off, shall we say, to install new exhaust valves and lap all valves, or perhaps some home porting, wouldn't .017 be "acceptable" for this type of build?
not to me . We used to run .0005 clearance w/o a seal on the hemi , never had a problem w/it !~
My victor type heads had about .001 - .0015 when new, no problems -
rustycowll69
Well-Known Member
guides are only 1/2 the equation. Sure the guides need to be straight, & round w/no taper, but the valve stems need to be straight, round w/no taper, too.
I use my valve grinding pilots to check guide size. I actually have a Chrysler tool, which is kind of a short sleeve to slip over the valve stem before you slide the valve into the guide to hold the valve head off of the seat a set amount to check for wobble like they show in the FSM. I rarely use it, though, because it's only made for stock valves and stock heads, and I feel I have acquired a better feel for what kind of clearance I'm looking for anyway.
I use my valve grinding pilots to check guide size. I actually have a Chrysler tool, which is kind of a short sleeve to slip over the valve stem before you slide the valve into the guide to hold the valve head off of the seat a set amount to check for wobble like they show in the FSM. I rarely use it, though, because it's only made for stock valves and stock heads, and I feel I have acquired a better feel for what kind of clearance I'm looking for anyway.
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